Anionic polymerization of vinylaromatic monomers offers significant advantages over free radical polymerization because the polymer is more pure and better quality. However, the rate of polymerization is so rapid that high levels of solvent or special process technology is required in order to control the process. One of the most recent advances is to add a polymerization rate retardant to the process; see for example U.S. Pat. No. 6,350,834.
Relevant prior art includes:
U.S. Patents                U.S. Pat. No. 5,902,865—Preparation of polystyrene by continuous anionic polymerization        U.S. Pat. No. 6,444,762—Anionic polymerization process        U.S. Pat. No. 6,350,834—Method for retarded anionic polymerization        U.S. Pat. No. 6,429,273—Process for the preparation of vinylic polymers, polymerization initiator for vinylic monomers, and styrene resin composition        
Publications                Initiation of Styrene Retarded Anionic Polymerization Using the Combination of Lithium Alkoxides with Organometallic Compounds, Menoret, Stephane; Fontanille, Michel; Deffieux, Alain; Desbois, Philippe; Demeter, Juergen. Laboratoire de Chimie des Polymeres Organiques, Macromolecules (2002), 35(12), 4584        Retarded anionic polymerization; 5. influence of the structure of dialkylmagnesium additives on the reactivity of polystyryllithium species, Menoret, Stephane; Carlotti, Stephane; Fontanille, Michel; Deffieux, Alain; Desbois, Philippe; Schade, Christian; Schrepp, Wolfgang; Warzelhan, Volker, Macromolecular Chemistry and Physics (2001), 202(16), 3219        Towards the control of the reactivity in high temperature anionic polymerization of styrene: retarded anionic polymerization; 3. influence of triisobutylaluminum on the reactivity of polystyryllithium species, Desbois, Philippe; Fontanille, Michel; Deffieux, Alain; Warzelhan, Volker; Schade, Christian, Macromolecular Symposia (2000), 157(International Symposium on Ionic Polymerization, 1999), 151        
However, in the prior art the retardant additive can not be removed from the polymer resulting in high cost and poor quality polymer. It would be an advance in the art if a process were invented whereby the retardant additive could be removed from the polymer and then recycled.